Them. this online community intended to empower commu- nity residents to increase their involvement in their self-management and pushing the active participation in phycial activities. function such as reminder of activity participating was added. future study will be conducted to evaluate changes in health promotion self-efficacy, health goal fulfillment, health-related quality of life, and shared decision-making p10-04 effects of a web-based versus a print-based physical activity intervention for community-dwelling older adults: results of a randomized trial with a cross-over design background despite the crucial role of regular physical activity (pa) for preventing chronic non-communicable diseases, fewer than half of older adults in germany engage in the recommended levels. objective: the aim of this study was to compare acceptance and effectiveness of two interventions for pa promotion among initially inactive community-dwelling adults aged 60 years and above in a nine-month randomized trial with a cross-over design. methods participants were recruited offline and randomized to (a) a print-based intervention (print n = 113) and (b) a web-based intervention (web, n = 129). thirty percent (n = 38) of those in group (b) received a pa tracker in addition to web (web+, (c)). all intervention groups were offered ten weekly face-to- face group sessions led by trained student assistants. afterwards, participants could choose to stay in their group or cross over to one of the other groups. group sessions were continued monthly for another six months. three-dimensional accelerometers to assess pa at baseline (t0), three-months (t1) and nine-months (t2) were employed. intervention acceptance was assessed via self-administered paper-based questionnaires. linear mixed models were used to calculate differences in moderate-to-vigorous pa (mvpa) between time points and intervention groups. results of the initially recruited n = 242 participants, n = 91 (37.6%) were randomized to the web group, n = 38 (15.7%) to web+ and n = 113 (46.7%) to print and n = 195 participants completed t1. only n = 1 moved from web to print and n = 15 from print to web (web-web: n = 103, print- print: n = 76), when offered to cross over at t1. one- hundred and sixty participants completed t2. mvpa in min per day increased between baseline and t1, but these within- changes in time disappeared after adjusting for covariates. mvpa decreased by 9 min/day between baseline and t2 ( b time = -9.37, 95% ci: [-18.58; -0.16]), regardless of intervention group (web vs. print: b time = -3.76,